/// 读入整数并且打印他们的平均值
/// 如果输入为空,不打印

#include<iostream>
#include<ostream>

int main() {
	int sum(0);
	int count(0);
	int x;
	while (std::cin >> x) {
		sum = sum + x;
		count++;
	}

	if (count == 0)
	  std::cout << "No data.\n";
	else 
	  std::cout << "average = " << sum / count << '\n';
}
